A (2;8) translocation, balanced, 46 chromosomes. Repository identification no. GM-845.
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to W E Bucknall.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Two families with unusual hexosaminidase A (HEX A) mutations are described. In one, the proband had the Tay-Sachs disease phenotype with considerable HEX A activity. In the second, the proband was phenotypically normal with absent HEX A activity. Activities using ganglioside GM2 as substrate demonstrate markedly reduced activities in the first case and half-normal activities in the second. Pedigree analyses indicate the presence of two different mutations. In the first, the proband appears to be an allelic compound HEX A 2-4 where mutation HEX A 4 leads to a diminution of HEX A activity against GM2 but not for the synthetic substrate, 4MU-beta-D-N-acetyl-glucosaminide, with HEX A 2 being the Tay-Sachs disease (or similar) mutation. In the second family, the proband is an allelic compound HEX A 2-5 where mutation HEX A 5 leads to a diminution of HEX A activity against the synthetic substrate, 4MU-beta-D-N-acetyl-glucosaminide, but not for GM2. The presence of either mutation will lead to false-negative (HEX A 4) or false-positive (HEX A 5) assignments of heterozygosity or homozygosity for GM2 gangliosidosis when synthetic substrates are employed. In both families, DM2 N-acetyl-beta-D-galactosaminidase activity in fibroblasts was an accurate determinant of phenotype.
Explore the source record for details and available documents.
Ten human ribosomal core proteins examined electrophoretically showed significantly less polymorphic variation than expected on the basis of other protein systems studied. This implies that selective forces may restrict variation at these loci. Variation in common multigenic traits must be determined by a combination of common alleles. If there is restriction of variation at certain types of loci, a limit is placed on the number of loci which can play a role in multigenic inheritance. Surveys for polymorphism in groups of proteins with similar structural or functional roles will further define these limits.
Explore the source record for details and available documents.
Explore the source record for details and available documents.